Albert p



(No Model.)

A. P. MASSEY.

AIR BRAKE.

No. 451,409. Patented Apr. 28, 1891.

To QAXXAYUX WITNESSES m: mums FETERG 0a., "momma wAsnmuTcu, n. c.

UNITED STATES PATENT FFICE.

ALBERT P. MASSEY, OF VATERTOWN, ASSIGNOR TO THE EA'MES VACUUM BRAKECOMPANY, OF NE\V YORK, N. Y.

AIR-BRAKE.

SPECIFICATION forming part of Letters Patent No. 451,409, dated April28, 1891.

Application filed October 13, 1890. Serial No. 368,043- (No model.)

To aZZ whom it may concern: ward stroke without a material reduction inBe it known that I, ALBERT P. MASSEY, a the air-pressure below it.citizen of the United States, residing in the While in the positionshown in the drawcity of lVatertown, in the county of J effer- .ingthere is an open passage from the train- 5 5 son and State of New York,have invented pipe through port 9, around valve. 1 and certain new anduseful Improvemontsin Airthrough port to cylinder 19, and thence Brakes,of which the following, taken in conthrough the triple valve to theauxiliary resnection with the accompanying drawing, is ervoir, in theusual manner. Thereis also an a specification. open passage for theexhaust from the brake- 60 IO The object of my invention is to providecylinder through port 13, under slide-valve means in an automaticfluid-pressure railway- 18 through port l4: 16, and thence through brakesystem whereby the speed of trains the chamber above piston 2 and port 8to the descending'long and heavy grades maybe atmosphere. Thus myinvention in no wise controlled without the employment of the interfereswith the functions of the triple 65 r 5 usual pressure-retaining valvefor the retenvalve in ordinary braking.

tion of a determined low pressure in the The operation of my inventionin accombrake-cylinders. plishing the object claimed is as follows:Theaccompanying drawingisaview, partly When the pressure in thetrain-pipe is in in longitudinal section and partly in elevacreased apredetermined amount above the 7,0 tion, of my improvement applied to anordinormal-say ten orfifteen poundsthe pressnary quick-actionfluid-pressure-brake valve, ure on the under side of piston 2 willexceed commonly called a triple valve. My imthat of spring 6 on theupper side and it will provement is shown as replacing the ordinary moveupward. The first thing done will be head or cap of the triple valve,although it is to close the exhaust-port 8 and the feed-port 75 notnecessarily placed in this position. 10, thus preventing thehigher-pressure air In the drawing, 2' is a piston exposed on frompassing to the triple valve, but without one side to the pressure of airin the trainproducing any change in the triple valve itpipe and on theother side to the pressure self. A little further upward movement willof spring 6, exerted through bell-crank 5 cause the slide-valve 1 toopen port 21, and 8o and links 4:. This piston opens and closes thusallow a little air to pass through port 21 port 8. Slide-valve 1, whichis moved by 22 23 to the chamber above piston 2,whicl1 is means of thelugs or projections on pistona portion of the exhaust-passage from therod 3, opens and closes ports 10 and 21. The brake-cylinder. Thereforethe air will pass pressure of spring 6 upon the upper side of throughport 16 15 11 under slide-valve 18 85 piston 2 is such that until thetrain-pipe and throughport 13 to the brake-cylinder and pressure isincreased a certain predetermined apply the brakes with whateverpressure may amount above the normal the downward pressbe in the chamberabove piston 2. The ure will exceed the upward pressure and pisamount ofair which will pass into the chamton 2 will be held against theprojection in her above piston 2 is determined by the ex- '90 40 thecylinder which is shown in the drawing. cess of the pressure belowpiston 2 over the By using the bell-crank 5 to transmit the pressure ofspring 6 on said p1ston,for when pressure of spring 6 to the piston 2 Iam enair which passes through port 21 22 23 has abled to keep thespring-pressure on the upper added suffic1ent pressure on top of piston2 side of piston 2 practically constant, for as to that already exertedby the spring it will 9 5 5 the piston 2 moves up and spring 6 is conrcause the piston 2 to descend until port 21 is pressed the pistonleverage increases, while closed, but not far enough to open exhaustthespring leverage decreases. In fact 1 adport 8. Thus the brakes Will havebeen apjust the angle between the leverages of bellplied with a slightpressure equal to the difcrank 5 so that the resistance of the springference between the traiirpipe pressure and r00 decreases slightly asthe piston rises, in order the pressure exerted by spring 6 on piston 2.that the piston may not travel its full down- A further increase in thetrain-pipe pressure will cause the piston 2 to move up again and allow alittle more air to pass through port 21 and apply the brakes a littleharder. Should the train-pipepressure be 110w decreased somewhat, butnot below the predetermined pressure necessary to overcome spring 6,piston 2 will move down and allow air to escape through port 8, when thepressure in the brake-cylinder will be reduced until the train-pipepressure will overcome the spring-pressure and that of the air stillremaining above piston 2 and cause piston 2 to rise su'lfieiently toclose exhaust-port 8 again, thus retaining a reduced pressure in thebrake cylinder. Should the train-pipe pressure be now reduced to thenormal, the piston 2 will return to the position shown in the drawing,thus opening port 8 and releasing the brakes, and also opening port 10,so that the train-pipe pressure has again access to the triple valve forthe purpose of actuating it in the usual way. Further, it will benoticed that while this apparatus is in action the auxiliary reservoirwill be charged to its normal limit, and therefore in case of a hosebursting or of the parting of the train the brakes will be automaticallyapplied with the highest pressure. The engineer can also at any timeapply the brakes in the normal way.

\Vhat I claim as new, and desire to secure by Letters Patent, is

1. The combination, with the triple valve and its casing, of asupplemental shell or chamber attached thereto, a brake-cylinderexhaust-passage leading to said chamber, a connecting-passage from thetrain-pipe to said exhaust-passage through said chamber, a port to thetriple-valve piston, a valve controlling said connecting-passage andtriple-valve port,

and a piston connected to said valve operated by train-pipe pressure,substantially and for the purpose described.

2. lhe con1bination,with the triple valve and its casing, of asupplemental shell orchamberattachedthereto,abrake-cylinderexhaustpassage leading to saidchamber, a connecting-passage from the train-pipe to saidexhaust-passage through said chamber, an exhaust-port from said chamber,a port to the triple-valve piston, a valve COl'ltlOlllllg.Slldconnecting-passage and triple-valve port, and a piston connected to saidvalve operated by train-pipe pressure, and also itself controlling theexhaust-port, substantially as and for the purpose described.

The combination, with the triple valve and its casing, of a supplementalshell or chamber attached thereto, a brake-cylinder exhaust-passageleading to said chamber, a connecting-passage from the train-pipe tosaid exhaust-passage through said chamber, a port to the triple-valvepiston, avalve controlling said connecting-passage and triple-valveport, a piston connected to said valve operated by train-pipepressure,and a spring connected to said piston through a rockinglever attached tosaid piston and spring, so that the leverarm of the spring grows shorteras the piston rises,substantially as set forth.

In testimony whereof I have signed my name to this specification, in thepresence of two subscribing witnesses, on this 17th day of September, A.D. 1890.

ALBERT 1. MASSEY. Witnesses:

HENRY W. Bovnn, HARRY G. MANNING.

